Primary histiocytic dermatoses.

Area of Science:

• Immunology
• Dermatology
• Pathology

Background:

• Histiocytes, also known as macrophages, play crucial roles in both health and disease.
• Histiocytic disorders encompass a spectrum from benign to malignant conditions.
• This review excludes Histiocytosis X but includes a broad range of other histiocytic diseases.

Purpose of the Study:

• To provide a concise overview of the physiology of histiocytes.
• To categorize and describe primary malignant, pseudomalignant, and benign histiocytic disorders.
• To highlight key features of various histiocytic conditions in adults and children.

Main Methods:

• Literature review and synthesis of existing knowledge on histiocytic disorders.
• Classification of histiocytic diseases into malignant, pseudomalignant, and benign categories.
• Description of specific conditions based on clinical and histological characteristics.

Main Results:

• Malignant histiocytosis with erythrophagocytosis is described.
• Pseudomalignant conditions such as sinus histiocytosis with massive lymphadenopathy and regressing atypical histiocytosis are detailed.
• Benign adult histiocytic diseases include histiocytic dermatoarthritis and xanthomatous eruptions; childhood lesions include juvenile xanthogranuloma.

Conclusions:

• Histiocytic disorders are diverse, ranging from rare malignant forms to more common benign presentations.
• Understanding the classification and characteristics of these disorders is essential for accurate diagnosis and management.
• This review consolidates information on various histiocytic conditions, aiding in their recognition and study.